The use of cellular telephones and wireless networks has become increasingly widespread. As the use of cellular telephones has increased, the number and quality of additional features made available with the cellular telephones has also increased. For example, some mobile stations (e.g., cellular telephones) are able to provide hybrid services by allowing users to participate in either voice calls or data sessions. In this way, a single, hybrid mobile station may provide the functionality of both a cell phone and a device that is operable to send and receive e-mail, text messages, or the like over a data network.
When the hybrid mobile station is in a data mode and a voice call for the mobile station is received at a corresponding mobile switching center (MSC), the MSC has to notify the mobile station of the incoming voice call so that the mobile station may switch over to a voice mode and the call may be established. Some current techniques for establishing a call in this situation include the MSC sending a Page Request message using an A1 interface to either the packet control function (PCF) unit or the base station handling the data session for the mobile station. Thus, this requires the use of an A1 interface between the MSC and each of a number of PCFs and/or base stations, which is relatively expensive to implement.
Furthermore, this type of feature that allows voice calls to be established for mobile stations operating in a data mode, in addition to other types of CDMA2000 features, such as Feature Activation/Deactivation, Message Waiting Indication, Registration, SMS Delivery, Position Location, and Status Inquiry, may not be available to mobile stations operating in the data mode under currently implemented systems.
Therefore, there is a need in the art for improved wireless networks that provide inter-working between formerly mutually exclusive technologies, i.e., the 1xEV-DO air interface and the CDMA2000 air interface. In particular, there is a need for a wireless network that is able provide CDMA2000 features to hybrid mobile stations operating in the data mode.